title: Regulation of C-type natriuretic peptides and natriuretic peptide receptor-B expression in diabetic rats renal treated by Tongluo Recipe.
abstract: OBJECTIVE
  To investigate the expression of C-type natriuretic peptides (CNP) and natriuretic peptide receptor-B (NPR-B) receptor in diabetic rats renal cortex, and the regulation by Tongluo Recipe (TLR).
  
  
  METHODS
  Sixty male SD rats were divided into 3 groups: the normal control group, diabetic model group and diabetic TLR group. Each group was further divided into two subgroups of ten in each, according to 4-week or 12-week observation period. Streptozotocin (STZ)-induced diabetic rats were treated with TLR (1.0 g·kg(-1)·d(-1)) for 4 and 12 weeks, respectively. (1) The essential information was collected for comparing renal mass, serum creatinine and 24 h urine albumen on each group was calculated. (2) CNP mRNA and NPR-B mRNA were detected by realtime-polymerase chain reaction (PCR) on rats renal cortex. (3) Concentration of CNP on renal cortex or serum were analyzed by enzyme-linked immunosorbent assay (ELISA). (4) Pathological evaluation and NPR-B immunostaining for renal tissue were also performed.
  
  
  RESULTS
  (1) CNP and NPR-B mRNA levels were detected in each treated or untreated group, with slight elevated in untreated diabetes rats administrated with STZ after 4-week and CNP mRNA level remarkable elevated at 39.21 times higher than normal control group after 12 weeks, but NPR-B mRNA level showed a remarkably down-regulation at 98.07% after 12 weeks. CNP mRNA of TLR-treated group was also elevated after 12-week treatment, but less than untreated group. (2) Concentrations of CNP in renal cortex were obviously increased in treated or untreated diabetes rats, within these groups the treatment of TLR was found more significantly on prompting CNP concentration. Comparing to normal group, serum concentrations of CNP were also increased in treated or untreated diabetic groups, but there was no difference between these diabetic groups. (3) Renal lesions like glomerular volume increased are observed mostly in the relative early stage after 4 weeks. Although TLR treated group had no significant difference in their glomerular volume, the degrees of injury of glomerulus were ameliorated, as well as the NPR-B immunostaining enhanced in glomerulus. Weakly positive immunostaining of NPR-B are observed in glomerulus of normal control, and negative in glomerulus of untreated diabetes rats administrated with STZ after 12 weeks, whereas TLR-treatment groups showed a little enhancement.
  
  
  CONCLUSIONS
  CNP and NPR-B showed different characteristic on renal cortex at different pathological period in diabetes rats, and TLR regulated their expression.
authors.affiliation: Department of Endocrinology, General Military Hospital of Jinan Military Region, Jinan 250031, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Qu
authors.forename: Zhao-Shun
authors.initials: ZS
authors.lastname: Jiang
authors.forename: Chun-Yang
authors.initials: CY
authors.lastname: Zhang
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Zou
authors.forename: Liang-Liang
authors.initials: LL
authors.lastname: Sun
authors.forename: Yong-Quan
authors.initials: YQ
authors.lastname: Shi
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Liu
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000188:drug therapy* / Q000235:genetics* / Q000473:pathology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology* / Q000627:therapeutic use; D005786:Gene Expression Regulation / Q000187:drug effects*; D006417:Hematuria / Q000150:complications / Q000235:genetics / Q000473:pathology; D007150:Immunohistochemistry; D007668:Kidney / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D007672:Kidney Cortex / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D007678:Kidney Glomerulus / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008297:Male; D020098:Natriuretic Peptide, C-Type / Q000235:genetics* / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017461:Receptors, Atrial Natriuretic Factor / Q000235:genetics* / Q000378:metabolism; D013194:Staining and Labeling; D013311:Streptozocin; D000099242:Atrial Natriuretic Factor Receptor B
chemical_list: D004365:Drugs, Chinese Herbal; D020098:Natriuretic Peptide, C-Type; D012333:RNA, Messenger; D017461:Receptors, Atrial Natriuretic Factor; D013311:Streptozocin; D000099242:Atrial Natriuretic Factor Receptor B; C527174:tongluo